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 ###Instrução: Qual é a primeira perna que tem 52-70 como a agregação?
 ###Tabelas: CREATE TABLE round_of_16 (round_of_16_id AUTO_INCREMENT PRIMARY KEY, Team 1 VARCHAR, Agg. VARCHAR, Team 2 VARCHAR, 1st leg VARCHAR, 2nd leg VARCHAR) CREATE TABLE top_20_countries_by_tally (top_20_countries_by_tally_id AUTO_INCREMENT PRIMARY KEY, Rank INT, Country/Territory VARCHAR, Miss World INT, 1st Runner-up INT, 2nd Runner-up INT, 3rd Runner-up INT, 4th Runner-up INT, 5th Runner-up INT, 6th Runner-up INT, Semifinalists INT, Total INT) CREATE TABLE bathurst_1000_results (bathurst_1000_results_id AUTO_INCREMENT PRIMARY KEY, Year INT, Number INT, Team VARCHAR, Co-driver VARCHAR, Position VARCHAR, Laps INT) CREATE TABLE current_usl_soccer-specific_stadiums (current_usl_soccer-specific_stadiums_id AUTO_INCREMENT PRIMARY KEY, Stadium VARCHAR, Club(s) VARCHAR, Division VARCHAR, City VARCHAR, Capacity INT, Opened VARCHAR) CREATE TABLE fire_station_locations_and_apparatus (fire_station_locations_and_apparatus_id AUTO_INCREMENT PRIMARY KEY, Station VARCHAR, Engine Company VARCHAR, Ambulance VARCHAR, Address VARCHAR, Phone VARCHAR)  
SELECT 1st leg FROM round_of_16 WHERE Agg. = 52-70